Auxiliary lock for doors and windows



W. C. PRATT AUXILIARY LOOK FOR DOQRS AND WINDOWS Aug. 4, 1925.

Filed April 2 1924 Patented Aug. 4, 1925.

OFFICE.

WELLIAM CORNER PRATT, .OF HORNSBY,.1\TEAR SYDNEY, NEW SOUTH WALES,AUSTRALIA.

AUXILIARY LOCK FOR DOORS AND WINDOWS.

Application 'filed April 2, 1924. Serial No. 703,777.

To all whom it may concern:

Be it known that 1, WILLIAM CORNER PRATT, a subjectoi' the King of GreatBrita-in, residing at l-lornsby, near Sydney, in the State of New SouthVales, Common wealth of Australia, have invented new and usefulImprovements in Auxiliary Locks for Doors and WVindows, of which thefollowing is'a specification.

This invention consists in a locking device usable on hinged doors andwindows, and also on sliding doors and windows, for securing the same infully, closed or par tially open position in such a way that they may bereleased for full opening to admit a person only by the action of aperson located within the apartment.

The device consists-of-a slotted metal arm which is detachably held in afixed staple secured to the door'or window jamb or frame and a latchlock fixed on the door or -window and adapted to co-act with said arm tolimit the extent of opening of the door .orfsash. The stub end of theslotted arm is ofl'setand is slid into a staple which is apermanent'fiXt-UIG'OD the post or frame. The bolt'of the latch is slotted so thatwhen partially retired the slots come to register with the edges of theslot in the bracket ;arm, permitting the door or sash to be opened onlyso far asthe slot extends, that Eis,-sufficient only for the purpose offacili- Ltating. ventilation. The part of the slot near the bent stubend oi the bracket arm is notched to offer sufiicient width to enablethe latch bolt to be shot and retired When the boit is extended or shotso that the slot in it comes beyond the edge of the bracket arm slot itacts as a lock to prevent "opening of the-door. As the latch boltcan beretired only when the door or sash is fully closed, access cannot 'behad to the apartment from outside. A keeper is fitted on the bracket armnear thestub end of it to engage zone "of the slots in the bolt andprevent withdrawal of the bolt even whilst "the door or window is infully closed position. This keeper must be released by a person withinthe apartment in order to iree the latch bolt, but it is resetautomatically when the latch-bolt traverses the slot in "the c'losingmovement of the door, so that when the door has been closed :the keeperis found restored to :its original position and the voluntary action ofa person closed position.

within the apartment is necessary to free the lock. Another keeper is inthe shapeiof a -check-paw l arranged at the inner .end of the slottedarm to engage the lock bolt and hold the door or window in the partialiyopen position to facilitate ventilation.

In the accompanying :drawings- Figure l is a perspective elevationalview showing the device fixed on a liinged Ldoor with the bolt partiallyshot and its slot-s engaged with the slot edges in the bracket arm; I

Figure 2 is a fragmentary rperspectiveelevational View showing theattachment arranged :as a sliding window check; and

Figure 3 is a fragmentary perspective view showing the bolt in the fullyshot position. 7

In the case of a hinged door or window, the slotted arm 10 is curved :tothe radius of the door or window sweep; in the case arm 10, and 12 the:notched portion of-same in register with the spring bolt "13 of thelatch when the door or window is in tally The stub end-of the z-slottedbracket arm 10 is bent to form a tang 14 which is slid into the fixedstaple 15. This staple is secured to the door frame or post 16 by ascrewor screws,rthe heads oi which are covered by the tang 14 when sameis inserted. The tang 14 is held in position in the staple 15 by meansof a screw 17.

The latch bolt 13 is housed in a casing 18 and the bolt is backed aspring which normally tends to force it outward. The casing is fixeditothe door or sash :byazscrew through its back plate, a hole-85being made 'in the case back to offer access 'to the :head *ofthis screwwhen the :bolt 13 is removed .from :its housing.

The tail of the bolt 13 is formed as a finger piece 19 to facilitate itswithdrawal. .A keeper freely pivotedat 21 to the housing 18 is providedfor engaging the :finger piece :19 :to :hold the bolt 13 in retiredposition :and to prevent it from engaging :the slotted bracket.

Attop and bottom the nose of the bolt 13 :is slotted as shown at :22 and.23. These and :the door. may then be swungopen with the bolt 13 engagedin the slot 11. The extent of opening of the door orwindow is thenlimited by the length of the slot 11,-

- suiiicient to accommodate not" only the thickness of the slottedbracket 10 but also the thickness of the keeper 25. The pivot 26 is sopositioned that in the fully closed position ofthe door or window theforward end of the keeper may set in the bolt slot 22. The keeper mustbe tilted upwardly to free its forward end from the bolt slot 22 beforethe bolt 13 canbe withdrawn to allow of the door or window to be openedto a greater extent than is permitted by the range of the, slot 11. Inthe opening movement, so long as the bolt 13v is in the position shownin Fig. 1, the keeper 2 1 is reset automatically and it does not becomereleased unlessmanipulated when the door or window is brought 'totheshut position.

On the keeper 20 being released the bolt 13 is shot by its spring. lVhenthe door or Window is normally shut and the keeper 25 "is tipped up (seeFig. 3), the bolt 13 will be fully shot through the notched portion 12of the slot 11 and will lock thedoor or window in the fully closedposition. If the bolt be withdrawn till its slots 22 and 23 registerwith the edges of the slot 11, the door or window may be swung open asfar as the length of the slot 11 permits, and until the door or windowhas been again brought to y the fully closed position and the keeper 25tilted to the free position and the bolt 13 withdrawn by the occupant ofthe apartment, it will not be possible for a person to enter theapartment from without. Even if the door or window be left opento thefull extent-permitted by the length of the slot 11, it would be uselessfor an intruder to insert his arm through the open portion and set thekeeper "25, for in the closing movement to bring the bolt 13 to theclear-, ance notch 12 at the base of the slot 11, the keeper will beautomatically reset at the locked position or will chock the bolt sothat it cannot enter the slot notch and the bolt cannot in either ofthese conditions be withdrawn. Perfect security for the occupant of theapartment is therefore assured. When the bolt is set back by means ofthe keeper, the device is inoperative and the door or sash may then beclosed and fully opened in the usual way. If the bolt be held backmanually the door or sash will be freed to open fully. 'Then if closedafter the bolt has been released by the hand the bolt will becomeautomatically r eengaged in the slot as soon as full closed position isreached.

In the case of the window latch type of fastener shown in Fig. 2,another form of keeper issubstituted for the swing keeper 20 shown inFig. 1. The keeper in this case may be a clip 30, the nose 31 of whichtakes over the end of the bolt 13 whilst its rear part is engaged by thethe upset tang 32 the normal locking means, and also as means forpermitting a limited movement only of i a door or window, or it may beused as a supplemental locking device operative with or independently ofother latching or look ing devices. F

What I do claim is:

1. A locking device'for limiting the degree of opening of doors andWindows and for fastening the same in closed position, comprising abracket arm with closed end longitudinal slot therein, a latch boltdeeper than the width of the slot,and having slots across the top andbottom faces of its head which slots register with the edges of the slotin the bracket arm when the boltis partially shot, a clearance s ace forthe bolt head at the base of the brac et arm slot, and a keeperengageable' in one of the bolt nose slots and pivotally mounted on oneside of the bracket arm, with one end ofit disposed across saidclearancespaceto partly close said spacei 2. A locking device forlimiting the degree of opening of doors and windows, consisting of aspring latch bolt with cross slotted head co-acting with a closed. end aslot in a bracket arm by sliding engagement of the cross slots with theedges of I the bracketarm slot, a clearance space at one end of saidbracket arm slot to permit bolt movement therethrough to engage anddisengage the bolt and the bracket arm, and a pivoted keeper on thebracket arm engageable with one of the bolt cross slots anddisengageable therefromonly whilst the bolt is in register withtheclearance space.

3. A locking device for limiting the degree of opening of doors andwindows, consisting of a slotted bracket arm 10 with staple mountingtang 14, a clearance way 12 at the base of the slot 11 in alignment with1.

the bolt head 13 in the closed position of the door or window, a springlatch bolt 13 having its head cross notched at 2223 to register with theedges of the slot 11, a keeper 25 pivotally mounted at 26 rearward ofthe lock bolt, and with its inner end projecting across the clearancespace 12, means for manipulating the bolt 13 and for checking it inretired position and a check pawl 24 adapted for chocking the bolt inthe fully open position of the door or window, said keeper 25 adapted toreset automatically in the closing movement of the door or Window tohold the bolt engaged by it at the clearance space until said keeper 25is manipulated from within the apartment to clear the bolt and permitits retirement, substantially as described.

In testimony whereof I aflix my signature in the presence of twowitnesses.

WILLIAM CORNER PRATT.

Witnesses N. STABPEID, R. BOULTON.

